mcnutt



Nov. 9

J. F. MCNUTT AUXILIARY TRANSMISSION FOR MOTOR VEHCLES 2 sheets-snee' Filed April 23. 1925 INVENTOR: J E MSA/n,

ATTORNEY.

Nov. 9 41926.

. 1,605,967 J. F. McNuTT y AAUXILIARY 'FRANSMSSION FOR MOTOR VEHICLES Filed April 23, 1925 2 Sheets-Sheet 2 INVENTOR.'

ATTORNEY.

Patented Nev. 9 i532@ ldiiillTE-D STEELS Mmm JOHN F. MCNUTT, A1CIE' GLENBALE, AiGAI..JFDRNIA..

AUXILIARY TRANSMISSION FOR MOTOR VEHICLES.

.Application led April .23, .1925. (Serial No. 25,355.

The invention relates .to improved trans mission devices, especially suitable to use 1n motor vehicles, for effecting changes of speeds relatively between fthe `power shaft and the driven shaft or axle. The invention effects this by novel utilization of an oscillatab'le shaft, driving pinion and internal gear, to the end that special advantages are attained in my device, enabling its ready utilization `with a minimum of difficulty, "as welll kas attaining special functional advantages, overcoming .numerous objections to prior devices in which an-oscillatable shaft, pinion and `internal :gears have been employed.

A further special object of my invention is to provide an embodiment adapted to use as an auxiliary transmission in certain motor vehicles of well known type, the need for which auxiliary is well understood in the art.

An important attainment of lthe invention consists in enabling` theA lateral movement and also longitudinal shifting of the gear with a single control lever in a novel and emeient manner, adapting the device to sustain the stresses or drive and torque with a minimum liability of failure or excessive friction and wear. A further aim is to provide a novel construction of mounting for a laterally and longitudinally reciprocable gear. A further aim is to `provide a novel construction of `bralre applicable to use in devices of this kind. A. still further object is to present a novel mounting for a gear shift lever suitable for use upon fauxiliary transmissions of this character.

Additional objects, advantages and features of invention reside in the details of construction, and the combination and .relative arrangement of parts,.as will be readily understood from the following description and accompanying drawings, wherein- Figure l is an elevational view of the drive shaft housing or tubeand differential housing upon which my invention has-been incorporated.

Figure 2 is an enlarged longitudinal sectional view of the mechanism while in high speed position. f

Figure 3 is a view of the gears and mounting only, in neutral positioinwhile Figure l is a view similar to Figure v3 showing the parts in low speed position.

Figure 5 Vis a cross sectional view on the line A-A of FigureQ.

Figure '6 is a detailof tion.

Figure T is a fragmentary perspective of the mounting of the brake shaft and adjustjing means.

Figure S is a cross section on the -line B-B of Figure 2.

Figure 9 is a perspective view ofa 2port-ion of 'the gear-shifting means.

Thestructure with which my invention 'is used as an auxiliary includes, as is well `known, a differential housing l, a power or drive shaft28, and a drive sha-ft housing or tube 2l, las shown in Figure l, usually supported at `the rear end on a drive shaft roller bearing housing, not shown, which is `abutted against a suitable machined face on the differential housing. My invention as e1nfbodied 'here includes which is substituted for the ordinary drive shaft roller'bearinghousing, and also a case 3 secured to the Vbearing housing 2, the case havinga forward sleeve extension in which Athe rear end portion of the drive shaft housing 4l may `be brazed .or otherwise secured after being cut off or othewise shortened, 4as required. In place-of 'the ordinary shaft ofregular equipment, I provide va correspondingly shortened drive shaft A28 as shown in Figure 2, having splines ,upon the `rear endand extending a suitabledistance.

The usual bevelled driving pinion 33 is keyed upon `the Vrear end of a driven shaft 31, which -is mounted inthe bearing housing 2 fbymeans'of a roller bearing 32 of ordinary form at the rear part, and an :adjustable bearing at the forward part, the cone element of which is mountedupon the hub of a'drum 27, which is -keyed upon the forward tapered vend of the shaft 31, the race 28 Vof the last named bearing being mounted in an adjusting sleeve 29, suitably Vthreaded and screwed `into a cylindrical flange at the l`forward lside of the housing 2, being se 4cured -in adjusted positions by a lock screw 34 engaged through the housing 2 from the outside.4 The drum includes a head vp0rtion substantially planiform and in a plane at right angles Ito the axis Vof the shaft 31, and awall 4portion'which is cylindrical Iand smoothly finished inside and out. A brake yis provided, acting upon this drum, includ ing -ra `suitably vfaced Vmetal band 35 pivotally supported atr-one'end between ear-s3? within and upon lthe case,'the opposite yend of the "band being lthe brake Abland seca .bearing lhousing 2' lprovided with a vertically slotted upstanding lug 36 in which is laid the brake shaft 42 supported at its inner end in a bossed bearing 38 formed on the case, being projected through the opposide side ofthe case where it is supported in a sleeve 43 externally threaded and screwed into the side of the case, projected inwardly to engage a cam 41 supported revolubly on the shaft and having a lateral arm receiving a stud 48 slidable therethrough by which the cam is prevented from turning, the stud being carried by the case. A lock nut 44 is provided on the sleeve 48. A cam sleeve 40 is pinned upon the shaft to cooperate with the cam 41, having a plane face engaged with the lug 3G whereby the thrust produced by rotation of the shaft is communicated to the brake band. in arm 10 is pinned to the lshaft 42 which may be connected by the brake rod 11 to one of the usual brake operating appliances of a motor vehicle, in the present instance being shown connected to the arm 13 of the usual brake lever shaft 12, the brake lever being omitted from the views.

Small and large internal gears 25 and 26 are provided within the drum 27, having a pressed fit therein and being keyed therein in any familiar way, the smaller gear being next to the head of the drum or at the rear, and having teeth of the same pitch, approximately, although the smaller gear does not require to have hypocycloidal form, as it is intended to serve solely as a clutch to receive snugly a spur driving gear 24. The gear 24 is longitudinally slidable on the splined portion of the shaft 28, being shown asformed with anintegral sleeve extended forwardly therefrom and fitted to the shaft. This gear supports the rear end of the shaft 28 and is itself in turn mounted in a carriage 21 supported for longitudinal and vertical reciprocation, as will appear. The gear sleeve is mounted in the carriage by means Y of roller bearings22 of ordinary form, one

at the rear side of the carriage, and the other at the forward side, the sleeve projecting forwardly a short distance beyond the cone element of the forward bearing 22, being externally threaded and provided with adjusting and lock nuts 23 by which compensation for wear may be effected as required. r1`he lever 19- is supported on a horizontal shaft 50 extending transversely through the lower part of the case 3 and thisshaft serves as a rest for the carriage at the rearward and lower limit of its movement, as shown in Figure 2. Forward movement of the carriage is limited by means of a lug` 49 formed on the lower part thereof which will strike the shaft 50, the lug being extended downwardly a distance to continue in engagement with the shaft 5 0 when `the carriage is raised, as will be described. The carriage is provided at its upper side with an integral vertical extension having a cam slot 51 therethrough having the upper rear and lower forward lobular portions. The lever 19 is provided with a lug or pin extending transversely through the slot 51 and having mounted thereon a roller or wiper 20 which is movable from one lobular port-ion of the slot 51 t0 the other and reverse. The forward side of the upper part of the slot has a slight slope forwardly and downwardly to its junction with the lowerl portion of the slot, as may be clearly seen in Figure 4, the purpose of which will be readily understood for the function ing of the device, as will be described. lllhen the carriage is at the rear and lower limit of its movement, the roller Q0 lies in the upper lobular part of the slot 51-not in supporting engagement, but on the contrary, a clearance is afforded by reason of which when the lever 19 is moved forwardly the carriage may slide upon the shaft 50 as before mentioned until the lug 49 engages that shaft. The lever 19 is moved by means of a shift rod 6, having a rear vertically slotted head receiving the outer end of the pin 52 upon which the roller 20 is carried. This rod is mounted in a bracket fitting 17, bolted on the forward side of the case 3, which is apertured to receive the rear end of the brackettherewithiir rllhe rod 6 .projects from the forward end of the bracket and a packing 18 is provided ther-eat to retain lubricant within the case properly. The bracket is formed with an upward extension bored and closed by a plug 16 screwed thereinto, which is utilized to retain a spring 15 bearing upon a ball 14 adapted to engage in respective notches 47 formed in the upper side of the rod 6 by which it may be held yieldingly in the different positions required in the operation of the device. rlfhe forward ond of the rod 6 is provided with an adjustable yoke to which is connected the usual link or shift rod 7 extending from the gear shift hand lever. 8, which is mounted upon a bracket 9 clamped upon the forward end of the tube 4.

The shaft 50 is supported in the case by means of adjustable sleeves 45 closed at their outer parts. It is important to note that the carriage 21 is formed on each side adjacent the level of the shaft 28 with vertical planiform bearing faces parallel to the axis of the shaft, and the lever 19 is similarly faced on each side at about the saine level, so that its inner bearing face may rest snugly against the adjacent bearing face of the carriage. For accurate centering of the rear end of the shaft 28 and gear 24 with respect to the drum, plugs 46 aie screwed through suitable bosses in the side of the case 3, Vthese plugs having smoothly machined flat inner faces adapted to snugly abut the outer lateral face of the carriage, on one recaen?? side, Dand the `corresponding face of the lever 19 on the other, thereby preventing loese lateral Vhorizontal movement of the `parts within the case, and also enablingthe `parts to be very accurately centered.

It should be noted that the lower lobular `portion of the slot 5l has its upper side located at such a height as to rest snugly upon the roller 20 when the carriage'is at `the forward upper limit of its movement, with the gear 24 snugly meshed with the upper portion of the large internal gear 2G.. rlhe case 3 may be closed kby a removable plate 30 bolted upon the top thereof, and it will be noted that all parts are of a character to be readily accessible and replaceable. Renewal of the brake-band may 'be effected without dismounting of the case or transmission parts, and adjustment of the brake may be effected without opening of the case or disturbance of any of the parts, except the sleeve 43 and the lock nut, rotation `of which will effect the required adjustments. It will also be observable lthat all of the parts required are of a simple and practical form adapted to be produced readily by the utilization of ordinary shop practices and are liable in a minimum degree to breakage or excessive wear.

lin the operation of this device, the lever 8 may be left constantly either in position for low speed drive or for high speed drive while the usual transmission of the vehicle in which it is installed is employed in the usual way. However, in case the regular transmission is of the planetary type, as is generally the case in the cars in which my appliance is ordinarily installed, a great deal of friction is involved whic-h makes cranking of the motor difficult in cold weather and also affords great retardation of the movement of the car in coasting at which time my device may be permitted to remain in neutral. In case braking of the car is then required, the location of the brake device as shown in my invention is of special value in enhancing the safety of the vehicle, as is readily appreciated by those versed in current practice. Shift from low to high or from high to low gear in my device may be accomplished by my device while the vehicle is in motion by releasing the clutch of the regular transmission while the lever 8 is operated to effect the change of gear positions required.

VVit-h the parts as shown in Figure 2, which is high speed position, the lever 8 will be at the rearward limit of its movement. the intermediate position dotted in Figure l. the rod 6 will be drawn forward, moving the upper end of the lever likewise, and by the roller 2O engaging the forward, side of the upper lobular portion of the slot 51 the carriage will be thrust forwardly, slid- Upon movement of the lever 8 to ing vupon "theshaft 50 until checked bythe lug 49, at which `time the iball 14 will also engage the intermediate recess 47 of the rod 6, and these two together will tend to :check further forward movement of the lever by holding the same .until additional .force is Aapplied thereto. By such. further movenient of `the lever 8 to the forward position dotted `in Figure l, the roller 2O is caused to bear against Vthe forward inclined surface of the upper portionof the slot, and as forward movement of the carriage is now prevented `by engagement of the lug 49 with the shaft 50, the effect will be to cause the 4roller 20 `to lift Ithe carriage and moveto the lower forward extension of the slot 5l., the upper side of which Iis approximately horizontal and will support the carriage in -position with the gear 24 properly engaged with the gear 26. It will be seen by this that the limited `space required for "the movement of the gear 24- froin the plane of one internal gear to the plane of the next is also utilized to effect the additional required movement to bring the gear 24 `laterally into engagement with the larger internal gear, at the same time that it is made possible to retain the gear 24 in a central position in the larger gear disengaged from both gears in the drum.

Complicated movement or forms in any of the parts has also been avoided by this construction, and the parts required for the auxiliary installation of this kind reduced to a minimum, as well as enabling the production of the appliance in an extremely compact and light form, without sacrificing the requirements of sturdy and rugged strength which are so desirable in transmissions of this kind. Thereby the unslung` weight is not objeotionably augmented and undue strain on standard axles, wheels and tires is also avoided.

As is well known in such a construction, the drive shaft tube is provided with integral lateral ears at the forward part, by which radius rods of the rear running gear are secured ordinarily, and it will be noted in Figure l that the bracket 9 upon which the lever 8 is mounted, is provided with corresponding ears at its forward part alined with those of the tube a, and receiving commonly the forward threaded end of the radius rod, as usual. The bracket extends rearwardly from this part over the tube, and an ordinary U-shaped clamping yoke is secured around the tube and through the bracket in a way familiar in such devices.

l claim:

l. In an apparatus of the character described, a laterally and longitudinally shiftable driving pinion including a bearing carriage movable therewith, and a driven meinber including gears alternatively engageable with the pinion at respective positions of the ica latter,v an intermediate member movable in a fixed path, means to reciprocate the last named member in such path, a stop for the carriage at one limit of its longitudinal movement, cam and wiper elements being incorporated in said carriage and intermedi ate member respectively whereby certain cam parts will move the carriage by reciprocation of said intermediate member over a part ot its path but so inclined that under stoppage of longitudinal movement ot the carriage and movement of the intermediate member eyond said part of its path the cam portion will lcoact with the wiper under their relative movement to move the carriage laterally.

2. ln apparatus ot' the character described, an oscillatable driven shaft, a gear having a sleeve in fixed relation thereto slidably splined on the shaft, said sleeve being exteriorly threaded at its extremity, a carriage for movement oi' the gear as required, roller bearings between the sleeve and carriage at opposite sides of the latter, and adjusting nuts on the extremity of the sleeve.

3. In apparatus of the character described,a case, a driven gear mounted on a iXed a-Xis therein7 a driving gear shiftable laterally and longitudinally, one of said gears having portions ot' different diameters to mesh with the other at different relative positions, a carriage for the shit'table gear including a cam part, a wiper movable in a path parallel to the neutral axis of the gears, said cam having a face inclined to the path, means to support the carriage slidably, and means to limit longitudinal movement ot the carriage to less than that of the wiper in one direction.

si. In a device of the character described, a case, a carriage having reciprocal movement in two directions, means to move the carriage, and means to guide the carriage comprising bearing plugs screwed in the side of the case having plani'form faces to guide the parts moving therebetween, means to move the carriage comprising a lever movable between the carriage and the bearing plug at one side, said lever having parallel sides and said carriage having parallel faces iitting snugly the lever and other plug.

In `testimony whereof I altix my vsignature.

JOHN F. MCNUTT. 

